1, the original design intention of dual clutch
The dual clutch itself was developed for racing cars. At the beginning of research and development, we only focused on the quick upshift function brought by its shift structure. As for service life, it is not an important factor to consider. The advantages of dual clutch are obvious, such as low cost, smooth and rapid upshift and small engine power loss, especially the engine power loss caused by dry dual clutch is almost zero.
2. Successful marketing strategy
At present, the dry dual-clutch gearbox developed by Volkswagen has made great progress since the frequent problems in 2009, which is better than the dual-clutch gearbox used by other brands. Volkswagen Group also calls the turbocharged engine with engine oil matching dual-clutch gearbox a golden combination, which has been successfully implanted in the minds of our people. Moreover, in the test drive experience, the steady speed-up of the dual-clutch gearbox really hit a consumer, which is why the advantages and disadvantages of the dual-clutch are very obvious, but it can be rampant.
3. Some people say that dual clutch is very good. Look at BBA's choice.
Let's take a look at how BBA brand chooses dual clutch. Mercedes-Benz GLA-class low-profile models use dual clutches, while other S, C and E classes use their own 9AT automatic gearboxes, while BMW does not use dual clutches. Audi A4, A6 and Q5 adopt dual clutch gearboxes, and high-end A8 and Q7 adopt 8-speed AT automatic gearboxes. The above verification can only show that the manufacturer knows well, and no matter how advanced the car is, the dual clutch can't be smashed.
4. Volkswagen stays away from the secret of AT automatic gearbox.
Why can an industrial country like Germany produce Mercedes-Benz BMW but not develop a mature at automatic gearbox? In fact, the world-famous AT automatic gearbox ZF is made in Germany, and Volkswagen also understands that at automatic gearbox is more stable and durable than dual clutch. However, the entrance of Audi ag reproducing at automatic gearbox has been blocked by ZF, Aisin and Jieke, and there is no other way for Volkswagen to study dual clutch. German Volkswagen's dual clutch gearbox has set up its own gearbox department according to the technology of Borgwarner. Because the dual-clutch gearbox is naturally fast, high in wear and short in service life, the biggest difficulty of various brands of dual-clutch gearboxes at present is to find a way to solve this problem.
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So there is so much controversy about the dry dual-clutch gearbox. Can we buy it? Dual clutch gearbox has been demonstrated in the market for more than ten years. We consumers should look at this problem rationally. Although the dual-clutch gearbox does have inherent technical defects compared with the ordinary AT gearbox, from the current performance of the dual clutch, there are also 1.5 thousand kilometers without any problems. However, to be fair, it is not easy for ordinary people to buy a car. Please try to stay away from the dual clutch gearbox.
Now DQ200 is the third generation, and the failure rate is very low. You can consider buying. Suitable for home use, and not as bad as those on the Internet. In fact, many poor people have never driven Volkswagen's dual clutch, or some domestic cars are equipped with dual clutch, which is the most test of factory training experience. Although the domestic car is well equipped, the gearbox and engine are far from being well tuned. Volkswagen's overall car experience is ok. I'm also the owner of dq200, and it's almost 80,000 kilometers. No problem. It was purchased in 65438+2006. At present, 1.4T is equipped with 7-speed dry dual clutch dq200, 7-speed wet dq38 1 gearbox and four-wheel drive. Everything else is new now. The high and low power of the 2.0T engine are all matched with the 7-speed wet gearbox. The torque is divided into dq38 1 and dq500, which are very good gearboxes. Dq38 1 is used for wet 7-speed dual clutch of cars, and dq500 is generally used for suv four-wheel drive.
China car owners love and hate Volkswagen powershift. At one time, Volkswagen powershift became an indelible shadow in the hearts of China car owners. Speaking of powershift, it can be said that it is frightening. When friends around me plan to buy a Volkswagen powershift, they will always try their best to block it. "The power shift is often overheated, the transmission is often damaged, and the worst thing is that the power shift is not repaired well." How can you buy such symptoms? This is the deepest impression left by Volkswagen powershift to China consumers 10 years ago, and the reputation of poor reliability of Volkswagen powershift comes from this.
But so far, Volkswagen powershift has developed for nearly 20 years. During this period, Volkswagen has been committed to the improvement of powershift and has never stopped. Volkswagen powershift has also made a major breakthrough. So far, China car owners seem to have gradually forgotten the trauma caused by Volkswagen powershift.
Every year, the total sales volume of Volkswagen Group in China automobile market has reached more than 4 million vehicles, more than half of which are equipped with powershift, and the proportion of powershift is also increasing year by year. Based on Volkswagen's confidence in China brand, almost 99% of Volkswagen's models are equipped with powershift and powershift as long as they match turbocharged engines, which is irreversible.
Volkswagen also took great pains to develop powershift, and repeatedly conducted various tests to adapt to the special road conditions in China. Volkswagen vehicles can be seen in Turpan, Heihe, Golmud, Tibet and other harsh working conditions every year. Undoubtedly, Volkswagen is also seriously developing its own vehicles, so as to make clear as far as possible the negative impact of Volkswagen powershift on the China automobile market.
Judging from the current transmission situation, the durability and stability of Volkswagen powershift, especially dry powershift, have been significantly improved. Although it can't be said to be perfect, at least it is no problem to meet the driving conditions of China car owners, such as traffic jams, fast overtaking and so on. So now Volkswagen Group, from high-end Audi brands to entry-level Skoda vehicles, adopts powershift.
What revolutionary technologies did Volkswagen adopt for powershift?
Because powershift has the most problems, it is more convenient to shift gears frequently in the first gear and the second gear in the low speed area. For example, in traffic jams, vehicles often stop and go. But now the public is also very smart. When the 7DCT transmission stops, it will automatically stop in the second gear by default, so that when the vehicle starts, it will not happen frequently in the first and second gears at low speed.
In dry power shifting, high temperature is very easy to occur when the clutch is rubbed, but the cooling mode of the clutch is air cooling, which has a good heat dissipation effect. Therefore, it is especially important to choose materials with good wear resistance and fast heat dissipation.
I wonder what you think of Volkswagen powershift? Welcome to leave a comment!
In addition to manual gears, AT, CVT, powershift and powershift have simple structures and the highest plasticity.
AT is quite old, and it is only a matter of time before it is eliminated. Why do you see it? The structure is complex, the economy is poor and the cost is too high, which can not meet the competition among enterprises. Needless to say, CVT is too rubbish to comment on. Dual clutch is a combination of manual transmission, with simple and reasonable structure, excellent economy and good maneuverability. Because some manufacturers have software programming that needs further optimization, they often feel frustrated at low speed.
AT and CVT will be in a downward trend in the next few years until they are eliminated. The ex-factory price of AT is much higher than that of dual clutch. With the maturity of dual clutch, AT has a living space. There is no reason not to use a dual clutch gearbox with excellent economy, simple and reasonable structure and good maneuverability.
After so many years of development, the stability and reliability of Volkswagen dual-clutch gearbox have been greatly improved. If you usually drive in the city, it is recommended to buy a wet dual-clutch model. The stability and reliability of wet dual-clutch model are better than that of dry dual-clutch model. If you usually take high-speed or many national highways, it is not too much of a problem to buy a dry dual clutch. It should be noted that the Volkswagen 1.4T turbocharged model is equipped with a dry dual clutch. All models above 1.8T adopt wet dual clutch. I hope I can help you!
Dry dual clutch is extremely unreliable from principle to application. The public regards China people as fools who don't understand cars. Fortunately, Volkswagen has been operating in China for many years. There are many employees in the factory, many shops in 4S, and many people who rely on maintenance to eat. Besides, there is no shortage of traitors in China since ancient times. If you are not fooled, you can put it aside. Aren't hundreds of millions of people without cars? Leek can be cut wave after wave. Ok, after that, what is dry dual clutch in principle? It is an open manual gearbox with automatic clutch stepping and computer logic shifting on the basis of manual gearbox. Its shifting principle is completely different from at and cvt. This brings the problem to 1: open air cooling. Unlike the exposed transmission gears and chains of variable-speed bicycles, the problem is that the transmission gears and chains of bicycles do not have to bear so much torque and speed, and there is no telex mechanism. I know what the durability and safety of the car wading gearbox will look like after it is flooded. 2. The open air-cooled dry dual clutch is not oiled and is controlled by computer logic. In theory, using manual gear will be faster than ordinary gear shifting, but it is also better than ordinary gear shifting, not necessarily better than professional drivers and old drivers. It's also a gimmick! Moreover, as the open dry gear and clutch plate are more prone to wear, the low gear is in a semi-clutch state, the logic problem of low-speed gear shifting, and the open, high-temperature and non-stop follow-up conversion of two clutches, it is inevitable for gears to work in this harsh working environment, and the meshing clearance between gears will increase, which is not only manifested in the frustration of the program, but also in the frustration of gear wear, and so on. Dry dual clutch is not only extremely unreliable in durability, but also nonsense!
I am a Volkswagen owner and have driven many dual-clutch models. I have mentioned similar questions in many answers.
The topic of dual clutch has been controversial, and some people love it and others hate it. You can say that dual clutch is not as easy, smooth and durable as at, or you don't like dual clutch, so you are determined not to buy Volkswagen. But if you specifically scold the Volkswagen dual clutch and don't scold other dual clutches, then there is a problem. Just as you can say that China is not as developed as the United States, you can't say that Beishangguangshen is inferior to the United States in all aspects.
DCT, AT, CVT are all good and bad, which varies from car to car. As a Volkswagen 6DSG owner and a Toyota 6AT owner who have tested the Volkswagen/Audi dual-clutch models above 10, I dare say that with the increasing bearing capacity of the Volkswagen dual-clutch, the shifting logic is becoming more and more perfect. If compared vertically, it can be said that a batch is not as good as a batch. Among the various brands of dual-clutch vehicles after 16, Volkswagen has the highest adjustment level, taking into account performance, efficiency, shift speed and ride comfort, and its driving performance is equivalent to at, which is in the middle and upper reaches. Especially in the following three aspects, the improvement is very obvious.
1. DSG will sacrifice a certain shift speed for ride comfort when driving in middle and low gears and gently. Especially in the process of 1 liter, 2 liters and 3 liters, we can feel the caution of gear shifting, and the balance between speed and smoothness is reasonable.
2. In the starting state, as long as it is not a big throttle, the car will soon rise to the second gear after moving, and as long as the speed is not lower than 5km/h, it will not return to 1 gear. Even at 5km/h, it will fall back to 1 gear, which is carried out by stepping on the clutch and the owner will not feel it. In this way, the frequent switching of 1-2 gears is avoided, and the riding comfort and power continuity in the initial stage are greatly improved. The disadvantage is that the starting power is weak, because in the speed range of 5- 12km/h, the second gear is in a semi-linkage state, and the power of the engine cannot be completely transmitted to the wheels.
3. In addition, the phrase "upshift is king, downshift is death" in the early days of dual clutch is no longer applicable on new DSG cars in recent years. 38 is right. Only when the internal gear pin pair is correctly positioned (guess the next gear you want to choose) can the dual clutch realize fast and smooth gear shifting. Before DSG, the driving environment accumulated in China was not rich enough, and the adjustment ideas were too simple and extensive. For example, if you accelerate smoothly in 4th gear, ECU always foolishly guesses that you will shift up later, so you put 5th gear on the odd gear transmission shaft in advance. In this way, you need to accelerate overtaking quickly, so go back to third gear. When the gearbox found that something was wrong, it had to decouple the fifth gear pin pair in a hurry and shift to the third gear again, which made it easy for the shift to rise to A B. However, with the accumulation of calibration experience and the progress of technical level, the current DSG is more and more intelligent and the calibration logic is more and more delicate. It will combine all the details of your driving data to judge which gear you need next, and the probability of guessing wrong is very small. Take LaVida as an example. If you suddenly step on the accelerator at a uniform or quasi-uniform speed (provided that you step deeply enough), even if you step down to the coaxial gear, you will be quick, and the ride comfort will not lose the mainstream A-class car of the same level.
For my Wei Lan and the 7th generation Camry, only 0-5km/h is the absolute smoothness of the Camry 6AT, and Wei Lan 6DSG must have a slight perceptible jitter. In other working conditions, the ride comfort of the two cars is actually similar to that of the other two cars. Wei Lan is the inevitable retrogression caused by the hasty combination of the clutch when the throttle is released from the D gear and then refueled, and the degree is positively related to the throttle depth. Camry has obvious power interruption in D gear 4 liters and 5 liters, which also caused inevitable setbacks. The degree is negatively related to the engine temperature (the colder the car, the more depressed it is), which should be because the power distribution of planetary gear sets is different from other gears.
As for the later reliability, my own car is only three years and 50 thousand kilometers, which is unconvincing. What we can see at present is sagitar 1.4T bought by our good friend 13, which is the batch of torsion beams with broken shafts, mainly in urban areas. At present, there has been no gearbox failure and deterioration of driving quality for seven years. My wife and best friend bought LaVida 1.4T in 2005. Although it is not long, it has run more than 654.38+10,000 kilometers, and the urban expressway is equally divided. There is nothing wrong with the gearbox at present. Frankly speaking, the cases around me are not necessarily representative, but what I want to say is that the longer the car is, the greater the influence of personal driving habits on the service life. For the same car, the reliability difference will gradually widen due to the different driving habits and use environment of the owner. Therefore, in terms of long-term reliability, I can never guarantee any car, even if it claims to be passed on to the next generation of Toyota.
Volkswagen dual clutch is divided into dry type and wet type. Wet dual clutch has no overheating problem, so it is a perfect structure by nature. Therefore, the wet dual clutch has always been reliable in the past and now, while the dry dual clutch has hidden dangers, such as frequent lifting of the first and second gears and overheating. However, after years of upgrading, the current dry dual clutch is still passable!
Now the life of DSG is guaranteed, and it is not as fragile as in the past, but it also scores; If it is true, compared with the life limit of At gearbox, then DSG must be finished first, but this range is large, and you may need to change cars before reaching this limit; Therefore, there is no problem for the current DSG to cope with normal use. The annual installed capacity of Volkswagen DSG is about 3 million units (the annual sales volume of Volkswagen is10 million units, 60% of which are in our domestic market). If such a huge base is still as fragile and troublesome as before, it is really a scene that the repair shop is not enough, but it is not like that!
Why is dry dual clutch easy to overheat?
In fact, the dual clutch is similar to the hardware structure of our manual gear, so why is it that manual gear and frequent first and second gear switching will not overheat, while power gear shifting is easy to overheat? In fact, manual gear and frequent first and second gear switching will also generate a lot of heat, but manual gear does not have so much electronic control, so even if it is overheated, it will not cause too much loss, and dual clutch will not work. After all, it has electronic components, which will fail once the temperature is high, such as the dead flash of that year!
The principle is simple, that is, the transmission ratio between the first gear and the second gear is too different. As shown in the above figure (the transmission ratio of a six-speed transmission), the transmission ratio of the first gear is 4.3 1, and the transmission ratio of the second gear is 2.33, and the difference between them is nearly twice. Therefore, when one liter is two and two drops are one, the rotating speed of the synchronizer synchronized by friction is relatively high, so the heat generated by friction is relatively large; Let's give a simple example. For example, when we upshift at 2000 rpm in the first gear, because the transmission ratio of the second gear is twice that of the first gear, the speed will drop to about 1000 rpm instantly after the upshift, which is too big!
Although there is a speed difference between other gears during synchronization, the speed difference is relatively small because there is no big transmission ratio difference between first gear and second gear, so the dry dual clutch is most afraid of frequent switching between first gear and second gear! The frequent use of first gear and second gear is precisely the working condition of our running in the city, so there is no way to solve the problem of overheating of dry dual clutch for many years; In fact, the solution is very simple. When driving in urban areas and congested environments, just switch to manual mode and limit the gear to first or second gear to avoid frequent switching and overheating!
Volkswagen's upgrade lies in the adjustment of shift logic in the system. For example, even in automatic mode and low-speed driving, the system will limit the gear to the second gear, which actually avoids the problem of frequent switching between the first gear and the second gear and can avoid overheating; In fact, this measure is the same as that of switching manual mode in the above article, except that one is manual and the other is system control; In the final analysis, the dry dual clutch is not as strong as At, and it is not as fragile as AT, because it is really not suitable for our domestic road conditions. In the past, DSG was fragile, but it was ok to run high-speed and run hundreds of thousands of kilometers every day, because the expressway avoided frequent use of first gear and second gear, and our road conditions became more and more congested, causing many problems in the past, but now the dry double clutch can be used!
I haven't found any problems in use, so I still have to test drive myself. There are too many sunspot water forces on the internet, which is of no reference significance. My driving experience is the most important.
Worldwide, Volkswagen's dual clutch is still relatively reliable.